Liquid crystal displays are advantageous in being light, thin and low in power consumption, and have been widely used in modern information devices such as notebook computers, mobile phones, and personal digital assistants (PDAs).
FIG. 1 is a schematic view of a conventional array substrate of a liquid crystal display. The array substrate 110 of the liquid crystal display comprises a signal introducing region 111 and a display region 112. Data line pads 121 and scan line pads 131 are formed in the signal introducing region 111. Data lines 122 and scan lines 132 are connected respectively to the data line pads 121 and the scan line pads 131, and crossing regions between the data lines 122 and the scan lines 132 define a plurality of pixels P. External data signals and scan signals are inputted via the data line pads 121 and the scan line pads 131, and then transmitted to the respective pixels P through the data lines 122 and the scan lines 132.
During the process of forming the conventional array substrate of the liquid crystal display, defects such as breaking may occur in the data lines. For example, as shown in FIG. 1, the data line 122 is broken at a location D3 in the display region 112. In this case, data signals cannot be transmitted to the portion of the data line past the breaking point D3, which causes a line defect.
In order to repair the line defect, a conventional repair structure is provided. As shown in FIG. 2, a data line 122 comprises three portions, that is, a front data line portion 122a outside the display region for connecting with the data line pad 121, a display region data line portion 122b, and an end data line portion 122c outside the display region on a side away from the data line pad 121. In addition, repair lines 223 are provided peripheral to the display region 112 in the liquid crystal display, and arranged across the front data line portions 122a and the end data line portions 122c orthogonally. However, the repair lines 223 and the data lines 122 are provided in different layers and have an insulating layer in between so that they are not in connection normally.
When a break occurs at D4 as shown in FIG. 2, the front data line portion 122a and a repair line 223 are connected at the crossing point A, and the end data line portion 122c and the repair line 223 are connected at the crossing point B by laser melting. As a result, data signals on the data line can be transmitted to the repair line 223 via the point A from the front data line portion 122a and then to the data line under the breaking point D4 via the point B, and thus the line defect is repaired.
However, there are some problems in such a repair structure. For example, the array substrate has to be provided with some space for disposing the repair lines, thereby causing an area of a non-display region to increase. Moreover, when using the repair lines described above to perform repair, the repair lines per se have relative large resistance, and may cause distortion of the data signals.